JP2012149279A - Cvd apparatus and method for replacing raw material tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CVD apparatus in which a raw material tank in a raw material solution supply unit can be efficiently and safely replaced.SOLUTION: In a raw material solution part having a tank outlet valve, an inert gas supply line valve, a discharge line valve, a raw material solution supply line valve and a solvent supply line valve, the tank outlet valve, the inert gas supply line valve and the solvent supply line valve are connected to a linear main pipe perpendicularly extending upward from the discharge line valve toward the raw material solution supply line valve so that liquid remaining in a specific area surrounded by the tank outlet valve, the inert gas supply line valve, the discharge line valve, the raw material solution supply line valve and the solvent supply line valve voluntarily flows down toward the discharge line valve.

Description

  The present invention relates to a solution vaporization type CVD apparatus and a raw material tank replacement method, and more particularly to a technique suitable for a piping structure of a raw material solution supply unit.

Conventionally, RE-based superconductors (RE: rare earth elements) are known as a type of high-temperature superconductor exhibiting superconductivity at a liquid nitrogen temperature (77 K) or higher. In particular, an yttrium oxide superconductor (hereinafter, YBCO) represented by the chemical formula YBa ₂ Cu ₃ O _7-y is representative. For the formation of this YBCO thin film, for example, a chemical vapor deposition method (CVD: Chemical Vapor deposition method) is used in which a superconducting layer is formed by supplying a raw material gas to the surface of a base material to cause a chemical reaction. .

When superconducting wire is manufactured using the CVD method, since the raw material of the superconductor is a solid at room temperature with a low vapor pressure, a solution (raw material solution) in which the solid raw material is dissolved is vaporized in a vaporizer, and this vaporized raw material A method of supplying gas to the reaction chamber is employed. As the raw material solution, for example, a solution of a metal β-diketone complex (for example, dipivaloylmethane (DPM)) in a solvent of tetrahydrofuran (THF) is used. DPM) n A solution vaporization type CVD apparatus used in the above-described method is disclosed in, for example, Patent Documents 1 to 3.
A general solution vaporization type CVD apparatus is a vaporizer that vaporizes a raw material solution in which a solid raw material is dissolved in a solvent, and a raw material gas vaporized by the vaporizer is supplied to the surface of the substrate to cause a chemical reaction. A reaction chamber to be formed and a raw material solution supply unit for supplying the raw material solution to the vaporizer are provided.

  FIG. 9 is a diagram showing a piping structure of a raw material solution supply unit of a solution vaporization type CVD apparatus conventionally used by the present inventors. FIG. 9 shows the actual piping structure (positional relationship between the valve and the piping) almost faithfully with respect to the raw material solution supply section when forming the YBCO thin film, with the vertical direction being the vertical direction and the horizontal direction being the horizontal direction.

As shown in FIG. 9, the raw material solution supply unit 10 includes raw material solution parts 11 to 13, a raw material solution supply line L <b> 1 connected to the raw material solution parts 11 to 13 through predetermined piping, and an inert gas supply line L <b> 2. , A solvent supply line L3, a discharge line L4, and a solvent supply unit 14.
In the Y raw material solution section 11, a tank pressurizing valve VX1 and a tank outlet valve VX2 are connected to the raw material tank 111. The tank pressurization valve VX1 is connected to the discharge line L4 via the second discharge line valve VX9, and is connected to the inert gas supply line L2 via the second inert gas supply line valve VX8. On the other hand, the tank outlet valve VX2 is connected to the inert gas supply line L2 via the first inert gas supply line valve VX4, connected to the raw material solution supply line L1 via the first raw material solution supply line valve VX6, The first discharge line valve VX5 is connected to the discharge line L4, and the solvent supply line valve VX7 is connected to the solvent supply line L3.
Also, the piping from the tank pressurization valve VX1 to the second inert gas supply line valve VX8 or the second discharge line valve VX9 and the piping from the tank outlet valve VX2 to the first raw material solution supply line valve VX6 etc. The valve VX3 is connected by a bypass line.

A branch pipe L11 branched from the raw material solution supply line L1 is provided with a second raw material solution supply line valve VX10 and a mass flow controller MFC, and the raw material solution supplied via the first raw material solution supply line valve VX6. The flow rate can be controlled.
In addition, since the piping structure of Ba raw material solution part 12 and Cu raw material solution part 13 is the same as that of Y raw material solution part 11, illustration and description are abbreviate | omitted.

In the Y raw material solution section 11, when the raw material tank 111 is replaced, the valves VX1 to VX7 are closed, the raw material solution remaining in the specific region R surrounded by the valves VX2 to VX7 is removed, and highly toxic The residual gas must be diluted with inert gas.
For example, after the first discharge line valve VX5 is opened to discharge the raw material solution, the solvent supply line valve VX7 is opened to fill the solvent. These steps are repeated a predetermined number of times to replace the raw material solution remaining in the specific region R with a solvent. Next, after the bypass line valve VX3 and the second discharge line valve VX9 are opened and evacuated, the bypass line valve VX3 and the second inert gas supply line valve VX8 are opened and filled with an inert gas. These steps are repeated a predetermined number of times to evaporate and exhaust the solvent remaining in the specific region R, and replace the residual gas with an inert gas. Then, the raw material tank 111 is disconnected at the connecting portion (joint) 112 and the raw material tank 111 is replaced.

JP-A-7-268634 JP-A-10-195659 JP 2001-332540 A

However, in the piping structure shown in FIG. 9, when the raw material tank 111 is replaced, deposits of solid raw material are scattered on the joint 112 of the raw material tank 111. In this way, when deposits are generated at the joint 112 of the raw material tank 111, the mass flow controller MFC is clogged during the supply of the raw material, making it impossible to control the flow rate of the raw material solution, or to check the ejection nozzle of the vaporizer. Clogging may occur and it may be impossible to eject the raw material solution. In this case, the ejection nozzle of the vaporizer is replaced, and the solvent supply line valve VX7, the first raw material solution supply line valve VX6, the second raw material solution supply line valve VX10, and the second switching valve VA2 are opened to the piping. It is necessary to wash the solvent for a long time.
Further, when the raw material tank 111 is replaced, liquid leakage may occur at the joint 112 on the tank outlet valve VX2 side. In this case, it is necessary to install a safety device such as a liquid tray or local exhaust.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a CVD apparatus and a method for replacing a material tank that can efficiently and safely replace a material tank in a material solution supply unit.

The invention according to claim 1 forms a thin film by vaporizing a raw material solution in which a solid raw material is dissolved in a solvent, and supplying a raw material gas vaporized by the vaporizer to the surface of the substrate to cause a chemical reaction. A CVD apparatus comprising: a reaction chamber; and a raw material solution supply unit that supplies the raw material solution to the vaporizer,
The raw material solution supply unit has a raw material tank having a raw material tank for storing the raw material solution; and
A raw material solution supply line for transporting the raw material solution sent from the raw material solution section to the vaporizer;
An inert gas supply line for supplying an inert gas to the raw material solution section;
A solvent supply line for supplying a solvent to the raw material solution section;
A discharge line for discharging the liquid or gas remaining in the raw material solution part,
A tank outlet valve connected to the raw material tank,
An inert gas supply line valve connected to the inert gas supply line;
A discharge line valve connected to the discharge line;
A raw material solution supply line valve connected to the raw material solution supply line;
A solvent supply line valve connected to the solvent supply line;
The liquid remaining in a specific region surrounded by the tank outlet valve, the inert gas supply line valve, the discharge line valve, the raw material solution supply line valve, and the solvent supply line valve naturally flows down to the discharge line valve side. The tank outlet valve, the inert gas supply line valve, and the solvent supply line valve are connected to a linear main pipe that extends vertically upward from the discharge line valve toward the raw material solution supply line valve. It is characterized by being.

According to a second aspect of the present invention, in the CVD apparatus according to the first aspect, a joining portion of the first branch pipe and the main pipe is connected to the tank outlet valve at the first branch pipe extending from the main pipe. The tank outlet valve is connected so as to be located below,
The inert gas supply line valve is connected to a second branch pipe that branches off from the main pipe so that a joint portion between the second branch pipe and the main pipe is positioned below the inert gas supply line valve. And
The solvent supply line valve is connected to a third branch pipe that branches off from the main pipe so that a joint portion of the third branch pipe and the main pipe is positioned below the solvent supply line valve. It is characterized by.

  According to a third aspect of the present invention, in the CVD apparatus according to the first aspect, each of the tank outlet valve, the inert gas supply line valve, and the solvent supply line valve is directly connected to the main pipe. It consists of a three-way valve.

  According to a fourth aspect of the present invention, in the CVD apparatus according to any one of the first to third aspects, the inert gas supply line valve is connected directly below the raw material solution supply line valve. Features.

According to a fifth aspect of the present invention, in the CVD apparatus according to any one of the first to fourth aspects, the raw material solution supply unit stores a drain tank that stores the liquid flowing down the discharge line, and the drain A discharge part having an exhaust pump connected to the discharge line via a tank;
The discharge line is inclined and connected to the discharge portion so that liquid naturally flows down the discharge line.

The invention according to claim 6 is the CVD apparatus according to claim 5, wherein the raw material solution supply part includes a solvent supply part that supplies the solvent to the raw material solution part via the solvent supply line,
The solvent supply unit is connected to the discharge line on the upstream side of the raw material solution unit.

Invention of Claim 7 is the replacement | exchange method of the said raw material tank in the CVD apparatus of Claim 1-6, Comprising:
A first step of discharging the liquid remaining in the specific region by reducing the pressure through the discharge line valve and a second step of filling the specific region with the solvent through the solvent supply line valve are performed a predetermined number of times. By repeating, discharging the raw material solution remaining in the specific region and replacing with the solvent,
The raw material tank is replaced after the solvent is removed.

Invention of Claim 8 is the replacement | exchange method of the said raw material tank in the CVD apparatus of Claim 1-6, Comprising:
A first step of discharging the liquid remaining in the specific area by depressurizing through the discharge line valve while supplying an inert gas through the inert gas supply line valve; and By repeating the second step of filling the solvent through the solvent supply line valve a predetermined number of times, the raw material solution remaining in the specific region is discharged and replaced with the solvent,
The raw material tank is replaced after the solvent is removed.

  The inventors presumed the cause of the above-described problem as follows. That is, in the piping structure shown in FIG. 9, the tank outlet valve VX2 and the first inert gas supply line valve VX4 are connected by a linear pipe extending in the vertical direction. In this pipe, upward from the tank outlet valve VX2, the joint 112 of the raw material tank 111, the horizontal pipe (bypass line) to which the bypass line valve VX3 is connected, the first discharge line valve VX5, 1 There is a joint β with a horizontal pipe to which a raw material solution supply line valve VX6 and a solvent supply line valve VX7 are connected.

The raw material solution remaining in the specific region R is discharged by opening the first discharge line valve VX5. However, in the region below the joint β, the liquid is difficult to be discharged due to gravity, so it is completely Is not discharged. Further, after discharging the raw material solution, the solvent is filled into the specific region R via the solvent supply line valve VX7. However, since the mutual diffusion of the liquid is not large, the raw material solution is not diluted in a short time. That is, there is a high possibility that the raw material solution remains in the region below the joint β without being completely replaced with the solvent.
For this reason, in the region below the joint β, it was speculated that when the solvent was evaporated in the evacuation step, the solid raw material was deposited and deposits were generated. In addition, since it is cooled by the evaporation of the solvent accompanying the decompression, it was assumed that in the region below the joint β, the solvent is difficult to evaporate, the liquid remains, and liquid leakage occurs. Under such assumptions, the present inventors have come up with the present invention by improving the piping structure to eliminate the portion where the raw material solution is less likely to be discharged due to gravity.

  According to the present invention, when the raw material tank is replaced in the raw material solution supply section, the raw material solution naturally flows down to the discharge line valve side, so that the raw material solution can be easily replaced with the solvent and the liquid remains in the pipe. Can be prevented. Therefore, when the solvent is evaporated by evacuation, no solid raw material is deposited, and no liquid leakage occurs when the tank is replaced. Therefore, the raw material tank can be replaced efficiently and safely.

It is a figure which shows schematic structure of the solution vaporization type CVD apparatus which concerns on embodiment. It is a figure which shows the piping structure of the raw material solution supply part which concerns on 1st Embodiment. It is a figure which shows the piping structure around a discharge part. It is a flowchart which shows an example of the raw material tank replacement | exchange process which replaces | exchanges a raw material tank. It is a figure which shows the open / close state of the valve | bulb in each step of FIG. It is a flowchart which shows another example of the raw material tank replacement | exchange process which replaces | exchanges a raw material tank. It is a figure which shows the open / close state of the valve | bulb in each step of FIG. It is a figure which shows the piping structure of the raw material solution supply part (Y raw material solution part) which concerns on 2nd Embodiment. It is a figure which shows the piping structure of the raw material solution supply part of the conventional solution vaporization type CVD apparatus.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of a solution vaporization type CVD apparatus provided with a vaporizer that vaporizes a raw material solution and supplies it to a reaction chamber. Here, an example of a CVD apparatus used for forming a YBCO layer is shown. In addition, in FIG. 1, the piping structure of the raw material solution supply part 10 is simplified and shown.

As shown in FIG. 1, a CVD apparatus 1 is a thin film formed by vaporizing a raw material solution obtained by dissolving a solid raw material in a solvent, and supplying a raw material gas vaporized by the vaporizer 20 to the surface of the substrate to cause a chemical reaction. And a raw material solution supply unit 10 for supplying the raw material solution to the vaporizer 20.
The raw material solution supply unit 10 supplies a Y raw material solution unit 11 for supplying an yttrium (Y) raw material solution, a Ba raw material solution unit 12 for supplying a barium (Ba) raw material solution, and a copper (Cu) raw material solution. A Cu raw material solution section 13 for supplying the solvent and a solvent supply section 14 for supplying the solvent.

The raw material tank 111 of the Y raw material solution section 11 contains Y (DPM) ₃ / THF in which a DPM complex of Y is dissolved in tetrahydrofuran (THF) as a solvent. The raw material tank 121 of the Ba raw material solution unit 12 stores Ba (DPM) ₂ / THF in which a DPM complex of Ba is dissolved in THF. The raw material tank 131 of the Cu raw material solution section 13 contains Cu (DPM) ₂ / THF in which a Cu DPM complex is dissolved in THF. The solvent tank 141 of the solvent supply unit 14 contains THF.
As the solvent, in addition to THF, organic solvents such as xylene, alcohols, ethers, ketones, amines and the like having a boiling point of 100 ° C. or lower and hydrocarbons can be used. Specifically, diethyl ether, diethyl ketone, ethanol, tetraglyme (tetraglyme), 2,5,8,11,14-pentaoxapentadecane and the like can be applied.

In the raw material solution supply unit 10, the raw material solution contained in the raw material tanks 111, 121, and 131 or the THF contained in the solvent tank 141 is pressurized by an inert gas such as He, Ar, and N _2. It is pumped out of the tank by raising it. In the raw material solution supply line L1, the raw material solutions Y (DPM) ₃ / THF, Ba (DPM) ₂ / THF, and Cu (DPM) ₂ / THF are mixed.
The mixed raw material solution is combined with a spray gas such as He, Ar, N _{2 and the} like, introduced into the vaporizer 20, and sprayed from the spray nozzle. The sprayed raw material solution collides with the inner surface of the vaporizer 20 and is instantly vaporized, and this vaporized gas is supplied to the reaction chamber 30 as a raw material gas together with O ₂ gas (not shown). The raw material gas introduced into the reaction chamber 30 is supplied to the substrate surface and chemically reacts to form a YBCO thin film.

  In the CVD apparatus 1 of the embodiment, the raw material solution parts 11 to 13 of the raw material solution supply part 10 have a characteristic piping structure. Specifically, it has the piping structure shown in the following first embodiment or second embodiment.

[First Embodiment]
FIG. 2 is a diagram illustrating a piping structure of the raw material solution supply unit according to the first embodiment. In FIG. 2, the actual piping structure (positional relationship between the valve and the piping) of the raw material solution supply unit 10 when forming the YBCO thin film is represented almost faithfully with the vertical direction being the vertical direction and the horizontal direction being the horizontal direction.

As shown in FIG. 2, the raw material solution supply unit 10 includes a raw material solution unit 11 to 13, a solvent supply unit 14, an inert gas supply unit 15, a discharge unit 16, and a raw material solution unit 11 to 13 or a solvent supply unit 14. It comprises a raw material solution supply line L1, an inert gas supply line L2, a solvent supply line L3, and a discharge line L4 that are connected via a predetermined pipe.
The raw material solution supply line L <b> 1 is a pipe for transporting the raw material solution sent from the raw material solution parts 11 to 13 to the vaporizer 20. The inert gas supply line L <b> 2 is a pipe for supplying the inert gas sent from the inert gas supply unit 15 to the raw material solution units 11 to 13 or the solvent supply unit 14. The solvent supply line L <b> 3 is a pipe for supplying the solvent sent from the solvent supply unit 14 to the raw material solution units 11 to 13. The discharge line L4 is a pipe for discharging the liquid or gas remaining in the raw material solution parts 11 to 13 to the discharge part 16.

A first switching valve VA1 connected to the vaporizer 20 and a second switching valve VA2 connected to the discharge line L4 are connected downstream of the raw material solution supply line L1 in the raw material solution transport direction. Only the first switching valve VA1 is opened during operation (when the raw material is supplied), and only the second switching valve VA2 is opened when the operation is stopped (such as when the raw material solution supply line L1 is washed).
A branch pipe L11 branched from the raw material solution supply line L1 is provided with a second raw material solution supply line valve VX10 and a mass flow controller MFC, and is supplied via a first raw material solution supply line valve VX6 described later. The flow rate of the raw material solution can be controlled.

In the Y raw material solution section 11, a tank pressurizing valve VX1 and a tank outlet valve VX2 are connected to the raw material tank 111. The tank pressurization valve VX1 is connected to the discharge line L4 via the second discharge line valve VX9, and is connected to the inert gas supply line L2 via the second inert gas supply line valve VX8. On the other hand, the tank outlet valve VX2 is connected to the inert gas supply line L2 via the first inert gas supply line valve VX4, connected to the raw material solution supply line L1 via the first raw material solution supply line valve VX6, The first discharge line valve VX5 is connected to the discharge line L4, and the solvent supply line valve VX7 is connected to the solvent supply line L3.
Also, the piping from the tank pressurization valve VX1 to the second inert gas supply line valve VX8 or the second discharge line valve VX9 and the piping from the tank outlet valve VX2 to the first raw material solution supply line valve VX6 etc. The valve VX3 is connected by a bypass line. By opening the bypass line valve VX3, the pressure on the inlet side and the outlet side of the raw material tank 111 becomes the same.

  In the first embodiment, the first raw material solution supply line valve VX6 and the first discharge line valve VX5 are positioned vertically with the first raw material solution supply line valve VX6 positioned upward and the first discharge line valve VX5 positioned downward. It is connected by a straight main pipe MP extending in the direction. That is, the liquid in the main pipe MP naturally flows down from the first raw material solution supply line valve VX6 side to the first discharge line valve VX5 side.

The main pipe MP is connected to straight branch pipes BP1 to BP4 extending in a substantially horizontal direction, and a solvent supply line valve VX7 and a tank outlet valve are connected to the other ends of the branch pipes BP1 to BP4. VX2, bypass line valve VX3, and first inert gas supply line valve VX4 are connected.
The branch pipe BP1 is disposed with a slight inclination so that the joining position with the main pipe MP is located below the solvent supply line valve VX7, that is, the solvent supply line valve VX7 side is located above. Similarly, the branch pipe BP2 is disposed slightly inclined so that the joining position with the main pipe MP is located below the tank outlet valve VX2, that is, the tank outlet valve VX2 side is upward. The branch pipe BP3 is disposed with a slight inclination so that the joining position with the main pipe MP is located below the bypass line valve VX3, that is, the bypass line valve VX3 side is located above. The branch pipe BP4 is slightly inclined so that the joining position with the main pipe MP is located below the first inert gas supply line valve VX4, that is, the first inert gas supply line valve VX4 side is upward. Arranged. That is, the liquid in the branch pipes BP1 to BP4 naturally flows down to the first discharge line valve VX5 side.

Further, a first inert gas supply line valve VX4 is connected immediately below the first raw material solution supply line valve VX6. Accordingly, the raw material solution or solvent remaining in the specific region R is supplied to the lower region by supplying the inert gas directly below the first raw material solution supply line valve VX6 via the first inert gas supply line valve VX4. It can be efficiently pushed toward the one discharge line valve VX5. That is, it is suitable when the raw material solution or solvent remaining in the specific region R is discharged while supplying an inert gas (see FIG. 6).
A solvent supply line valve VX7 is connected immediately above the first discharge line valve VX5. Thereby, since the solvent is filled in the specific region R from the lower side to the upper side, the solvent is supplied without interruption, and the deposits (for example, the raw material solution) in the pipe can be efficiently washed. .

  Thus, in the first embodiment, since the liquid remaining in the specific region R surrounded by the valves VX2 to VX7 naturally flows down to the first discharge line valve VX5 side, the raw material solution or the like is supplied to the branch pipes BP1 to BP4. There will be no problems caused by remaining.

In addition, since the piping structure of Ba raw material solution part 12 and Cu raw material solution part 13 is the same as that of Y raw material solution part 11, illustration and description are abbreviate | omitted.
In addition, the piping structure of the solvent supply unit 14 is not particularly limited, but in order to simplify the design and construction, the piping structure is generally the same as that of the raw material solution units 11 to 13. About each valve | bulb arrange | positioned at the solvent supply part 14, it has the same name as each valve | bulb of the Y raw material solution part 11, and it is set as the code | symbol VSn (n = 1-10). In the solvent supply unit 14, the solvent is sent to the raw material solvent units 11 to 13 through the tank outlet valve VS2 and the solvent supply line valve VS7. This point is different from the raw material solution parts 11 to 13 to which the solvent is supplied via the solvent supply line valve VX7.

As shown in FIG. 3, the discharge unit 16 includes a drain tank 161 that stores the liquid flowing down the discharge line L4 and an exhaust pump 162 that is connected to the discharge line L4 via the drain tank 161. The drain tank 161 is connected to the discharge line L4 via the drain valves VD1 and VD4, and is connected to the exhaust pump 162 via the drain valves VD2 and VD5. The drain valve VD4 and the drain valve VD5 are connected via the drain valve VD3.
The drain valves VD1 and VD2 are directly connected to the drain tank 161, and a joint connected to a line connected from the discharge line L4 to the exhaust pump 162 is located immediately above the drain valves VD1 and VD2. Therefore, when the drain tank 161 is removed, the drain valves VD1 and VD2 connected to the drain tank 161 are closed, and the joint immediately above the valve is opened. At this time, the drain valves VD1, VD2, and VD4 are closed and the drain valves VD3 and VD5 are opened so that the residual vapor of the source gas does not flow out from the joint portion, and evacuation is performed. When exhausting the Y raw material solution portion 11 and the like through the discharge line L4, the drain valves VD1, VD2, VD4, and VD5 are opened.

  Here, the discharge line L4 is connected to the discharge portion 16 so as to be inclined upward at an angle θ (for example, 5 to 15 °). Thereby, since the liquid discharged | emitted from the raw material solution parts 11-13 flows down the discharge line L4 naturally and is stored in the drain tank 161, the discharge line L4 is always hold | maintained in a clean state. For example, when the raw material solution or the like stays in the discharge line L4 for a long time, it is possible to prevent the solid line from being deposited and the discharge line L4 from being soiled.

  Moreover, the solvent supply part 14 is connected to the discharge line L4 upstream from the raw material solution parts 11-13. Thereby, after replacing | exchanging the raw material tank of the raw material solution parts 11-13, the discharge line L4 can be wash | cleaned easily. Specifically, the solvent supply unit 14 is opened by opening the tank pressurization valve VS1, the second inert gas supply line valve VS8, the tank outlet valve VS2, and the first discharge line valve VS5 of the solvent supply unit 14. Is sent to the discharge line L4 to wash the discharge line L4.

  Below, the process of forming a YBCO thin film on the base-material surface using the CVD apparatus 1 and the process of replacing | exchanging the raw material tank of the raw material solution parts 11-13 are demonstrated. In order to simplify the description, the Y raw material solution part 11 will be described, but the same process is performed in the Ba raw material solution part 12 and the Cu raw material solution part 13.

When the YBCO thin film is formed using the CVD apparatus 1, in the Y raw material solution section 11, the tank pressurization valve VX1, the second inert gas supply line valve VX8, the tank outlet valve VX2, and the first raw material solution supply line valve VX6 and the second raw material solution supply line valve VX10 are opened, and the other valves are closed.
An inert gas is supplied from the inert gas supply line L2 via the second inert gas supply line valve VX8 and the tank pressurization valve VX1, and the inside of the raw material tank 111 is pressurized. The pressurized raw material solution (Y (DPM) ₃ / THF) is pumped out of the tank through a dip tube in the raw material tank 111. The pumped raw material solution is transported through the tank outlet valve VX2 and the first raw material solution supply line valve VX6, and the raw material solution is supplied through the second raw material solution supply line valve VX10 while the flow rate is controlled by the mass flow controller MFC. Transported to line L1.
Then, after merging with other raw material solution and solvent in the raw material solution supply line L1, the raw material solution is supplied to the vaporizer 20 via the first switching valve VA1.

The replacement of the raw material tank is performed according to the flowchart of FIG. FIG. 5 shows the open / close state of the valve in each step of FIG. 4 (◯: valve open state, x: valve close state).
As shown in FIGS. 4 and 5, first, in step S101, all the valves of the Y raw material solution part 11 are closed, and the Y raw material solution part 11, the raw material solution supply line L1, the inert gas supply line L2, the solvent supply The connection with the line L3 and the discharge line L4 is cut off. The tank pressurization valve VS1 and the tank outlet valve VS2 of the solvent supply unit 14 are always kept open in the replacement process of the raw material tank 111 of the Y raw material solution unit 11.

  In Step S102, the first discharge line valve VX5 of the Y raw material solution section 11 is opened, and the specific region R surrounded by the valves VX2 to VX7 is decompressed, whereby the raw material solution or solvent remaining in the specific region R is discharged. . Also, the solvent supply line L3 is filled with a solvent so that the solvent supply line valve VS7 and the second inert gas supply line valve VS8 of the solvent supply part 14 are opened and the solvent can be immediately supplied to the Y raw material solution part 11. Keep it. And after predetermined time progress, the 1st discharge line valve VX5 of the raw material solution part 11 is made into a closed state, and discharge | emission of a raw material solution or a solvent is stopped (step S103).

In step S104, the solvent supply line valve VX7 of the Y raw material solution section 11 is opened, and the specific region R is filled with the solvent. And after predetermined time progress, the solvent supply line valve VX7 of the Y raw material solution part 11 is made into a closed state, and filling with a solvent is stopped (step S105).
Since the solvent supply line valve VX7 is connected immediately above the discharge line valve VX5, the solvent is filled with the specific region R facing upward. At this time, since the specific region R is in a reduced pressure state, the solvent is not interrupted in the piping of the specific region R. Therefore, the raw material solution remaining (attached) in the specific region R is easily diluted and finally replaced with the solvent.
By repeating steps S102 to S105 a predetermined number of times (for example, 3 to 5 times), the specific region R is almost completely replaced with the solvent.

Next, in step S106, the first discharge line valve VX5 of the Y raw material solution section 11 is opened, and the solvent filled in the specific region R is discharged. Then, after the predetermined time has elapsed, the first discharge line valve VX5 of the Y raw material solution section 11 is closed, and the solvent discharge is stopped (step S107).
In the processes after step S106, since it is not necessary to supply the solvent to the Y raw material solution section 11, the solvent supply line valve VS7 and the second inert gas supply line valve VS8 of the solvent supply section 14 are closed. It does not matter as it is.

  In step S108, the residual gas in the specific region R is exhausted by opening the bypass line valve VX3 and the second discharge line valve VX9 of the Y raw material solution section 11 and depressurizing (evacuating) the specific region R. When the solvent remains in the specific region R, the solvent is evaporated and exhausted by evacuation. And after confirming that the pressure of the specific area | region R became 1 kPa or less, for example, the 2nd discharge line valve VX9 of the Y raw material solution part 11 is made into a closed state, and vacuuming is stopped (step S109). Since the specific region R is completely replaced with the solvent by steps S102 to S105, the solid raw material does not precipitate when the solvent evaporates by evacuation.

In step S110, the second inert gas supply line valve VX8 of the Y raw material solution section 11 is opened, and the specific region R is filled with the inert gas. Then, after confirming that the pressure in the specific region R is, for example, 200 kPa, the second inert gas supply line valve VX8 of the Y raw material solution section 11 is closed to stop filling of the inert gas (step S111). ).
For example, when the pressure in the specific region R is reduced from 200 kPa to 1 kPa in step S108, and the inert gas is filled in step S110 to return the specific region R to 100 kPa, the residual gas in the specific region R is diluted to 1/200. Is done.
By repeating steps S108 to S111 a predetermined number of times (for example, 6 times), the specific region R is completely replaced with an inert gas.

  Next, in step S112, the bypass line valve VX3 is closed, and the preparation for replacing the raw material tank is completed. In step S <b> 113, the raw material tank 111 is disconnected from the joint 112 and replaced with a new raw material tank 111. At this time, since the raw material solution or the solvent does not remain in the specific region R (particularly, the joint 112), liquid leakage does not occur when the raw material tank 111 is replaced.

In step S114, the residual gas (air) in the specific region R is exhausted by opening the bypass line valve VX3 and the second discharge line valve VX9 of the Y raw material solution section 11 and depressurizing (evacuating) the specific region R. To do. And after confirming that the pressure of the specific area | region R became 1 kPa or less, for example, the 2nd discharge line valve VX9 of the Y raw material solution part 11 is made into a closed state, and vacuuming is stopped (step S115).
In step S116, the second inert gas supply line valve VX8 of the Y raw material solution section 11 is opened, and the specific region R is filled with the inert gas. Then, after confirming that the pressure in the specific region R becomes, for example, 200 kPa, the second inert gas supply line valve VX8 of the Y raw material solution section 11 is closed to stop filling of the inert gas (step S117). ).
By repeating steps S114 to S117 a predetermined number of times (for example, five times), the specific region R is completely replaced with an inert gas.

  Next, in step S118, this state is maintained for a predetermined time, and it is confirmed whether the raw material tank 111 is connected in an airtight manner (pressure test). When the pressure in the specific region R decreases, the raw material tank 111 is not airtightly connected, so that it is reconnected and the processes of steps S114 to S118 are performed again.

  In step S119, the bypass line valve VX3 and the second discharge line valve VX9 of the Y raw material solution section 11 are opened, and the specific region R is depressurized (evacuated), whereby a residual gas (inert gas) in the specific region R is obtained. Exhaust. And after confirming that the pressure of the specific area | region R became 1 kPa or less, for example, the 2nd discharge line valve VX9 of the Y raw material solution part 11 is made into a closed state, and vacuuming is stopped (step S120). In step S121, the bypass line valve VX3 of the Y raw material solution section 11 is closed, and preparation for raw material filling is completed.

  In step S122, the tank pressurization valve VX1, the tank outlet valve VX2, and the second inert gas supply line valve VX8 of the Y raw material solution section 11 are opened, and the raw material solution is pumped from the raw material tank 111 by the inert gas. The raw material solution is filled in the specific region R. In step S123, the second inert gas supply line valve VX8 of the Y raw material solution section 11 is closed, and the raw material filling is completed.

As described above, in the replacement process of the raw material tank 111 according to the flowchart of FIG. 4, the first process of discharging the liquid remaining in the specific region R by reducing the pressure through the first discharge line valve VX5 (steps S102 and S103). Then, by repeating the second step (steps S104 and S105) of filling the specific region R with the solvent via the solvent supply line valve VX7 a predetermined number of times, the raw material solution remaining in the specific region R is replaced with the solvent. Then, after removing the solvent (steps S106 to S111), the raw material tank 111 is replaced (steps S112 and S113).
After replacing the raw material solution remaining in the specific region R with a solvent, the replaced solvent is removed by evaporation, so that the raw material solution remaining in the specific region R can be efficiently discharged. Further, since the solid material does not precipitate when the solvent is evaporated by evacuation, the material tank 111 can be exchanged efficiently and safely.

The replacement of the raw material tank may be performed according to the flowchart of FIG. FIG. 7 shows the open / closed state of the valve in each step of FIG. 6 (◯: valve open state, x: valve closed state).
As shown in FIGS. 6 and 7, first, in step S201, all the valves of the Y raw material solution part 11 are closed, and the Y raw material solution part 11, the raw material solution supply line L1, the inert gas supply line L2, the solvent supply The connection with the line L3 and the discharge line L4 is cut off. The tank pressurization valve VS1 and the tank outlet valve VS2 of the solvent supply unit 14 are always kept open in the replacement process of the raw material tank 111 of the Y raw material solution unit 11.

In step S202, the first inert gas supply line valve VX4 and the first discharge line valve VX5 of the Y raw material solution section 11 are opened, and the inert gas is supplied to the specific region R surrounded by the valves VX2 to VX7. The raw material solution or solvent remaining in the specific region R is discharged. Also, the solvent supply line L3 is filled with a solvent so that the solvent supply line valve VS7 and the second inert gas supply line valve VS8 of the solvent supply part 14 are opened and the solvent can be immediately supplied to the Y raw material solution part 11. Keep it.
The raw material solution or solvent remaining in the specific region R is discharged from the discharge line L4 by natural flow while being pushed out to the lower first discharge line valve VX5 side by the inert gas, so that the raw material solution or solvent is efficiently discharged. can do.
Then, after a predetermined time has elapsed, the first inert gas supply line valve VX4 and the first discharge line valve VX5 of the Y raw material solution section 11 are closed, and the discharge of the raw material solution or the solvent is stopped (step S203).

In step S204, the first discharge line valve VX5 of the Y raw material solution section 11 is opened, and the specific region R is depressurized (evacuated), thereby exhausting the residual gas (inert gas) in the specific region R. And after confirming that the pressure of the specific area | region R became 1 kPa or less, for example, the 1st discharge line valve VX5 of the Y raw material solution part 11 is made into a closed state, and vacuuming is stopped (step S205).
In step S206, the solvent supply line valve VX7 of the Y raw material solution section 11 is opened, and the specific region R is filled with the solvent. And after predetermined time progress, the solvent supply line valve VX7 of the Y raw material solution part 11 is made into a closed state, and filling with a solvent is stopped (step S207).
By repeating steps S202 to S207 a predetermined number of times (for example, four times), the specific region R is almost completely replaced with the solvent.
The processes after step S208 are the same as the processes after step S106 in FIG.

As described above, in the replacement process of the raw material tank 111 according to the flowchart of FIG. 6, the liquid remaining in the specific region R is supplied to the first exhaust line while supplying the inert gas via the first inert gas supply line valve VX4. A first process (steps S202 to S205) for discharging by depressurizing via the valve VX5 and a second process (steps S206 and 207) for filling the specific region R with the solvent via the solvent supply line valve VX7 are predetermined. By repeating the process a number of times, the raw material solution remaining in the specific region R is replaced with a solvent. Then, after removing the solvent (steps S208 to S213), the raw material tank 111 is replaced (steps S214 and S215).
After replacing the raw material solution remaining in the specific region R with a solvent, the replaced solvent is removed by evaporation, so that the raw material solution remaining in the specific region R can be efficiently discharged. Further, since the solid material does not precipitate when the solvent is evaporated by evacuation, the material tank 111 can be exchanged efficiently and safely.

[Second Embodiment]
FIG. 8 is a diagram illustrating a piping structure of a raw material solution supply unit according to the second embodiment. In FIG. 8, only the piping structure of the Y raw material solution section 11 is extracted and shown, and the remaining configuration of the raw material solution supply section 10 is omitted because it is the same as that of the first embodiment.
In the second embodiment, the first raw material solution supply line valve VX6 and the first discharge line valve VX5 are positioned vertically with the first raw material solution supply line valve VX6 positioned upward and the first discharge line valve VX5 positioned downward. It is connected by a straight main pipe MP extending in the direction. Such a configuration is the same as that of the first embodiment.

In the second embodiment, the solvent supply line valve VX7, the tank outlet valve VX2, the bypass line valve VX3, and the first inert gas supply line valve VX4 are directly connected to the main pipe MP. This point is different from the first embodiment.
That is, the solvent supply line valve VX7 has a first communication port and a second communication port connected to the main pipe MP, and a third communication port connected to the pipe toward the solvent supply line L3. It is composed of a three-way valve capable of switching the supply of the solvent from the solvent supply line L3 in a state where the upstream side (for example, vertically upward side) and the downstream side are in communication.
Similarly, the tank outlet valve VX2 has a first communication port and a second communication port connected to the main pipe MP, and a third communication port connected to the pipe toward the raw material tank 111, and is upstream of the main pipe MP. It is composed of a three-way valve capable of switching the supply of the raw material solution from the raw material tank 111 in a state where the side and the downstream side are in communication.
The bypass line valve VX3 and the first inert gas supply line valve VX4 are a first communication port and a second communication port connected to the main pipe MP, and a third communication connected to the pipe toward the inert gas supply line L2. A three-way valve having a port and capable of switching the supply of the inert gas from the inert gas supply line L2 in a state where the upstream side and the downstream side of the main pipe MP are in communication with each other.

Further, a first inert gas supply line valve VX4 is connected immediately below the first raw material solution supply line valve VX6. Thereby, the raw material solution or solvent remaining in the specific region R is supplied to the lower first gas by supplying the inert gas from directly below the first raw material solution supply line valve VX6 via the first inert gas supply line valve VX4. It can be efficiently pushed toward the discharge line valve VX5. That is, it is suitable when the raw material solution or solvent remaining in the specific region R is discharged while supplying an inert gas (see FIG. 6).
A solvent supply line valve VX7 is connected immediately above the first discharge line valve VX5. Thereby, since the solvent is filled in the specific region R from the lower side to the upper side, the solvent is supplied without interruption, and the deposits (for example, the raw material solution) in the pipe can be efficiently washed. .

  The raw material tank replacement step in the second embodiment is performed according to the flowchart of FIG. 4 or FIG. 6 as in the first embodiment. In this case, the tank outlet valve VX2, the bypass line valve VX3, the first inert gas supply line valve VX4, and the solvent supply line valve VX7 are always in communication with the main pipe MP. That is, the open / close state of the valves shown in FIGS. 5 and 7 switches the communication state between the raw material tank 111, the inert gas supply line L2, or the solvent supply line L3 in each of the valves VX2 to VX4 and VX7.

  In the second embodiment, when the raw material tank 111 is replaced, the three joints 112 are separated and replaced. Therefore, the replacement work is complicated as compared with the first embodiment. Is greatly simplified compared to the first embodiment.

  Thus, in the second embodiment, since there is no dead space in which the raw material solution can remain at the connection portions of the valves VX2 to VX4 and VX7, the raw material solution remaining in the specific region R can be easily replaced with a solvent. it can. Further, since the raw material solution remaining in the specific region R is efficiently discharged by natural flow just by opening the first discharge line valve VX5, the raw material solution remaining in the main pipe MP is significantly reduced. . Therefore, there is no problem that the raw material solution remains in the specific region R.

As described above, in the first and second embodiments, the Y raw material solution unit 11 is connected to the tank outlet valve VX2 connected to the raw material tank 111 and the inert gas supply line L2. Gas supply line valve VX4, first discharge line valve VX5 connected to discharge line L4, first raw material solution supply line valve VX6 connected to raw material solution supply line L1, and solvent connected to solvent supply line L3 And a supply line valve VX7.
Then, a tank outlet valve VX2, a first inert gas supply line valve VX4, and a solvent supply are connected to a straight main pipe MP extending vertically upward from the first discharge line valve VX5 toward the first raw material solution supply line valve VX6. These valves are connected so that the liquid naturally flows from the line valve VX7 to the first discharge line valve VX5 side.
The bypass line valve VX3 can also be regarded as an inert gas supply line valve when it is opened simultaneously with the second inert gas supply line valve VX8. Further, the Ba raw material solution part 12 and the Cu raw material solution part 13 also have the same piping structure as the Y raw material solution part 11.

  According to the CVD apparatus 1, when the raw material tanks 111, 121, 131 are replaced in the raw material solution parts 11 to 13 of the raw material solution supply part 10, the raw material solution naturally flows down to the first discharge line valve VX 5 side. The raw material solution can be easily replaced with a solvent, and liquid can be prevented from remaining in the pipe. Therefore, when the solvent is evaporated by evacuation, no solid raw material is deposited, and no liquid leakage occurs when the tank is replaced. Therefore, the raw material tank can be replaced efficiently and safely.

  As mentioned above, although the invention made by this inventor was concretely demonstrated based on embodiment, this invention is not limited to the said embodiment, It can change in the range which does not deviate from the summary.

In the above embodiment, the case where the YBCO thin film is formed on the substrate surface has been described. However, the present invention is commonly applied to the case where the thin film is formed by the MOCVD method using a raw material having a low vapor pressure and a solid at room temperature. It is a technology that can be done. For example, the present invention can be applied to a case where an organic metal raw material in which a metal atom and an organic group are bonded through an oxygen atom is used as the solid raw material. Here, the organic group may be any one of acetylacetonate, dipivaloylmethanate, alkoxide, hexafluoroacetylacetonate, and pentafluoropropanoylpivaloylmethanate.
As raw materials for forming a ferroelectric thin film such as barium titanate or strontium titanate, barium dipivaloylmethanate (Ba (DPM) ₂ ), strontium dipivaloylmethanate (Sr) (DPM) ₂ ), bis (dipivaloylmethanate) diisopropoxytitanium (Ti (iPrO) ₂ (DPM) ₂ ”, etc. Also, titanium tetraisopropoxide (Ti (OC ₃ H ₇ )). ₄ ) The raw material which melt | dissolved etc. in THF may be sufficient.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 CVD apparatus 10 Raw material solution supply part 11 Y Raw material solution part 111 Raw material tank 12 Ba Raw material solution part 13 Cu raw material solution part 14 Solvent supply part 15 Inert gas supply part 16 Discharge part 20 Vaporizer 30 Reaction chamber 112 Joint L1 Raw material solution Supply line L2 Inert gas supply line L3 Solvent supply line L4 Discharge line MP Main piping BP1 to BP4 Branch pipe R Specific area VX1 Tank pressurization valve VX2 Tank outlet valve VX3 Bypass line valve VX4 First inert gas supply line valve VX5 1 discharge line valve VX6 first raw material solution supply line valve VX7 solvent supply line valve VX8 second inert gas supply line valve VX9 second discharge line valve VX10 second raw material solution supply line valve MFC mass flow controller VA1 first switching valve VA2 first 2 switching bar Breakfast VD1~VD5 drain valve

Claims (8)

A vaporizer that vaporizes a raw material solution in which a solid raw material is dissolved in a solvent; a reaction chamber that forms a thin film by supplying a raw material gas vaporized by the vaporizer to a substrate surface and causing a chemical reaction; and a vaporizer A raw material solution supply unit for supplying the raw material solution, a CVD apparatus comprising:
The raw material solution supply unit has a raw material tank having a raw material tank for storing the raw material solution; and
A raw material solution supply line for transporting the raw material solution sent from the raw material solution section to the vaporizer;
An inert gas supply line for supplying an inert gas to the raw material solution section;
A solvent supply line for supplying a solvent to the raw material solution section;
A discharge line for discharging the liquid or gas remaining in the raw material solution part,
A tank outlet valve connected to the raw material tank,
An inert gas supply line valve connected to the inert gas supply line;
A discharge line valve connected to the discharge line;
A raw material solution supply line valve connected to the raw material solution supply line;
A solvent supply line valve connected to the solvent supply line;
The liquid remaining in a specific region surrounded by the tank outlet valve, the inert gas supply line valve, the discharge line valve, the raw material solution supply line valve, and the solvent supply line valve naturally flows down to the discharge line valve side. The tank outlet valve, the inert gas supply line valve, and the solvent supply line valve are connected to a linear main pipe that extends vertically upward from the discharge line valve toward the raw material solution supply line valve. CVD apparatus characterized by the above-mentioned. The tank outlet valve is connected to a first branch pipe extending from the main pipe so that a joint portion of the first branch pipe and the main pipe is located below the tank outlet valve,
The inert gas supply line valve is connected to a second branch pipe that branches off from the main pipe so that a joint portion between the second branch pipe and the main pipe is positioned below the inert gas supply line valve. And
The solvent supply line valve is connected to a third branch pipe that branches off from the main pipe so that a joint portion of the third branch pipe and the main pipe is positioned below the solvent supply line valve. The CVD apparatus according to claim 1.   2. The CVD according to claim 1, wherein each of the tank outlet valve, the inert gas supply line valve, and the solvent supply line valve is a three-way valve that is directly connected to the main pipe. apparatus.   4. The CVD apparatus according to claim 1, wherein the inert gas supply line valve is connected immediately below the raw material solution supply line valve. 5. The raw material solution supply unit includes a drain tank that stores a liquid that has flowed down the discharge line, and a discharge unit that includes an exhaust pump connected to the discharge line via the drain tank,
5. The CVD apparatus according to claim 1, wherein the discharge line is connected to the discharge unit so that the liquid naturally flows down the discharge line. . The raw material solution supply unit includes a solvent supply unit that supplies the solvent to the raw material solution unit via the solvent supply line;
The CVD apparatus according to claim 5, wherein the solvent supply unit is connected to the discharge line upstream of the raw material solution unit. A method for replacing the raw material tank in the CVD apparatus according to claim 1,
A first step of discharging the liquid remaining in the specific region by depressurizing through the discharge line valve;
By repeating the second step of filling the specific region with the solvent via the solvent supply line valve a predetermined number of times, the raw material solution remaining in the specific region is discharged and replaced with the solvent,
A method for replacing a raw material tank, comprising: exchanging the raw material tank after removing the solvent. A method for replacing the raw material tank in the CVD apparatus according to claim 1,
A first step of discharging the liquid remaining in the specific region by reducing the pressure through the discharge line valve while supplying the inert gas through the inert gas supply line valve;
By repeating the second step of filling the specific region with the solvent via the solvent supply line valve a predetermined number of times, the raw material solution remaining in the specific region is discharged and replaced with the solvent,
A method for replacing a raw material tank, comprising: exchanging the raw material tank after removing the solvent.

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